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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fog/Mist

71°F

22°C

Humidity 96%
Wind Speed S 3 mph
Barometer 30.10 in (1018.8 mb)
Dewpoint 70°F (21°C)
Visibility 5.00 mi
Last update 16 Aug 6:52 am CDT
Extended Forecast for

Alto Pass IL

Heat Advisory August 16, 12:00pm until August 19, 07:00pm
Click here for hazard details and duration
Heat Advisory

  • Today

    Today: Patchy fog before 8am. Otherwise, sunny, with a high near 95. Calm wind becoming southeast around 5 mph in the afternoon.

    High: 95 °F

    Patchy Fog
    then Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 74. Light south southeast wind.

    Low: 74 °F

    Mostly Clear

  • Sunday

    Sunday: A 20 percent chance of showers and thunderstorms after 2pm. Sunny and hot, with a high near 98. Calm wind.

    High: 98 °F

    Sunny then
    Slight Chance
    T-storms

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 76. Calm wind.

    Low: 76 °F

    Mostly Clear

  • Monday

    Monday: Sunny and hot, with a high near 98. Light south wind.

    High: 98 °F

    Hot

  • Monday Night

    Monday Night: Mostly clear, with a low around 75. Calm wind.

    Low: 75 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny and hot, with a high near 97. Light west wind.

    High: 97 °F

    Hot

  • Tuesday Night

    Tuesday Night: A chance of showers and thunderstorms. Partly cloudy, with a low around 73. Light west northwest wind.

    Low: 73 °F

    Chance
    Showers

  • Wednesday

    Wednesday: A slight chance of showers, then a chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 89. North wind 5 to 7 mph.

    High: 89 °F

    Slight Chance
    Showers then
    Chance
    T-storms

Detailed Forecast

Today
Patchy fog before 8am. Otherwise, sunny, with a high near 95. Calm wind becoming southeast around 5 mph in the afternoon.
Tonight
Mostly clear, with a low around 74. Light south southeast wind.
Sunday
A 20 percent chance of showers and thunderstorms after 2pm. Sunny and hot, with a high near 98. Calm wind.
Sunday Night
Mostly clear, with a low around 76. Calm wind.
Monday
Sunny and hot, with a high near 98. Light south wind.
Monday Night
Mostly clear, with a low around 75. Calm wind.
Tuesday
Sunny and hot, with a high near 97. Light west wind.
Tuesday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 73. Light west northwest wind.
Wednesday
A slight chance of showers, then a chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 89. North wind 5 to 7 mph.
Wednesday Night
A slight chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 69. North wind 5 to 7 mph.
Thursday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 85. North northeast wind 5 to 7 mph.
Thursday Night
Mostly clear, with a low around 67. Northeast wind around 6 mph becoming calm in the evening.
Friday
Sunny, with a high near 87. North northeast wind 3 to 6 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Alto Pass IL
 37.57°N 89.32°W
Last Update:
5:30 am CDT Aug 16, 2025
Forecast Valid:
7am CDT Aug 16, 2025-6pm CDT Aug 22, 2025
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation